BEIJING/WASHINGTON - China scrambled jets on Friday in response to two U.S. spy planes and 10 Japanese aircraft, including F-15 fighters, entering its new air defense zone over the East China Sea, state news agency Xinhua said, raising the stakes in a standoff with the United States, Japan and South Korea.

The jets were scrambled for effective monitoring, Xinhua cited air force spokesman Shen Jinke as saying. The report gave no further details.